1. Field of the Invention:
The present invention relates to a method of mounting flexible tires on wheels, and apparatus for carrying out the method.
2. Description of Prior Art:
It has been customary in service shops to use simple tire changers for mounting tires on wheels. The tire changers, however, require a large number of steps for mounting tires, are not very durable in operation, and hence cannot be employed for use on automobile production lines. To cope with these problems, tire mounting machines have now found widespread use which have bead spreading rollers, a table lifter for moving the wheel up and down, and a rough guide attachment dependent on the size of a wheel which a tire is to be mounted. The wheel is laid flat over the table lifter, and the tire is half mounted on the wheel. Thereafter, the table lifter is raised by an actuator toward a stationary centering shaft. The shaft then engages in the hub hole of the wheel to align it, and the table lifter is then stopped.
In the position at which the table lifter is stopped, the lower surfaces of the bead spreading rollers are spaced from the rim of the wheel normally by a gap of 3 mm, and the bead spreading rollers project from the outer periphery of the wheel rim by a distance of 4 mm or more. With these gap and distance maintained, the bead spreading rollers are turned in the lefthand and righthand directions, respectively, through 180 degrees and turned back, for thereby mounting the tire on the wheel. If the gap and distance were smaller or larger than the indicated dimensions, the wheel would be injured and the tire bead would be damaged, resulting in less quality of the tire.
In order to keep the proper dimensions for the gap and distance, it has been necessary in the prior tire mounting machine that the table lifter, the centering shaft, and the bead spreading rollers be adjusted, and an attachment be employed which makes the dimension of the wheel to render the gap and distance constant for each wheel size. With this arrangement, where wheels of different sizes are randomly supplied to a tire mounting line, times required for positioning the various parts of the tire mounting machine become much longer and the rate of mounting the tires is extremely poor.